Hemp stripping machine

ABSTRACT

A plant stripping machine includes a casing with a longitudinal slot in the top of the casing. A pair of shafts are rotatably mounted within the casing. The pair of shafts are parallel and spaced apart defining a gap between the shafts aligned below the slot. The shafts counter rotate in relation to each other. A plurality of stripping members extend from and are spaced along the length of each shaft. The stripping members extend from the pair of shafts a radial distance sufficient to overlap within the gap. The pair of counter rotating shafts are arranged to engage and pull a plant with a stalk/stem portion and leafy biomass which is fed through the slot to between the shafts. The stripping members remove the leafy biomass from the stalk while leaving the stalk intact.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No. 62/942,794 filed Dec. 3, 2019 and U.S. Provisional Application No. 62/976,598 filed Feb. 14, 2020, which is hereby incorporated by reference.

FIELD OF DISCLOSURE

The present disclosure relates in general to harvesting equipment, and specifically deals with a machine and process for stripping leaves from the stalks of a hemp plant.

BACKGROUND

Humans have been using the hemp plant for thousands of years. Hemp is a fast growing plant and was one of the first plants to be spun into usable fiber 10,000 years ago. It can be refined into a variety of commercial items, including paper, textiles, clothing, biodegradable plastics, paint, insulation, biofuel, food, and animal feed. Oil can be obtained from the seeds, which can serve as a basis for a multitude of products. Using the hemp plant and its cultivation was commonplace until it was associated with its drug-type genetic sibling. Recently, there has been a reemergence of the hemp plant around the world. Cannabidiol (CBD) products are currently the center of an exploding market. CBD is obtained from the leafy biomass of the plant. As used herein, leafy biomass includes all the parts of the hemp plant excluding the stalk/stem, for example the leaves and flowers containing the plant's seeds.

Various methods and devices for separating the leafy biomass from the hemp stem are known. However, it is difficult to quickly and completely strip a hemp stem of its leafy biomass while maintaining a high yield rate. Therefore, it is desirable to have a simple, quick and efficient method and device to strip the leafy biomass from the hemp stems.

Thus, there is a need for improvement in this field.

SUMMARY

The present disclosure involves a plant stripping machine and process allowing a user to place a hemp plant into the machine wherein the leafy biomass is removed from the stalks. The user then pulls the stalks from the machine while the stripped material drops onto a conveyor belt which transports it for further processing.

The present machine includes an elongate casing having two ends and a pair of central ramp portions leading to a longitudinal entry slot. Arranged longitudinally below the respective ramp portions are a pair of rotating shafts. A plurality of stripping members extend radially and are spaced along the length of the shafts. Each shaft is rotationally driven.

The shafts are spaced so that the gap between them is below the entry slot and the stripping members radially overlap yet are longitudinally offset to alternate with each other. During operation, the shafts counter rotate so that the stripping members pull material downward between the two shafts and rotate upward on the outward sides. The stripping members are preferably made of slightly flexible materials, such as nylon forming a nylon cord. During operation, when a hemp plant is introduced through the entry slot, the stalks and leafy biomass pass between the shafts. While passing between the shafts, the stripping members function as flails to strip the leafy biomass from the stalks. The stripping members pull the leafy biomass downward while leaving the stalks intact. The stalks can then be withdrawn against the flailing of the stripping members, further ensuring that the stalks are completely stripped.

The floor of the machine is either open or forms a ramp leading to an exit opening optionally yet preferably arranged over a conveyor belt. The conveyor belt receives the leafy biomass that's been stripped from the stalks and transfers it away for further processing.

Further forms, objects, features, aspects, benefits, advantages, and embodiments of the present disclosure will become apparent from a detailed description and drawings provided herewith.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an example of a hemp stripping assembly including a hemp stripping machine and a conveyor assembly.

FIG. 2 is a perspective view of the hemp stripping machine of FIG. 1 in a tilted position.

FIG. 3 is a perspective view of the hemp stripping machine of FIG. 1 without the conveyor assembly.

FIG. 4 is a top view of the hemp stripping machine of FIG. 3.

FIG. 5 is a side view of the hemp stripping machine of FIG. 3.

FIG. 6 is a bottom view of the hemp stripping machine of FIG. 3.

FIG. 7 is a perspective bottom view of the hemp stripping machine of FIG. 3.

FIG. 8 is a perspective view of the hemp stripping machine of FIG. 3 with the covers removed.

FIG. 9 is a perspective view of a stripping assembly from the hemp stripping machine of FIG. 3.

FIG. 10 is an enlarged perspective view of a shaft of the stripping assembly of FIG. 9.

FIG. 11A is a cross-sectional view of the shaft of FIG. 9.

FIG. 11B is a cross-sectional view of another embodiment of the shaft of FIG. 9.

FIG. 12 is a perspective view of another embodiment of a shaft of the stripping assembly of FIG. 9.

FIG. 13 is an exploded view of the shaft of FIG. 12.

DESCRIPTION OF THE SELECTED EMBODIMENTS

For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles of the disclosure as described herein are contemplated as would normally occur to one skilled in the art to which the disclosure relates. One embodiment of the disclosure is shown in great detail, although it will be apparent to those skilled in the relevant art that some features that are not relevant to the present disclosure may not be shown for the sake of clarity.

The present disclosure involves a plant stripping assembly which is used to strip the leafy biomass from the stalk of a hemp plant. As used herein, leafy biomass includes all the parts of the hemp plant excluding the stalk/stem portion, for example the leaves and flowers containing the plant's seeds. The plant stripping assembly may include a plant stripping machine, a conveyor assembly and a support frame. The plant stripping machine will be described herein to strip a hemp plant. It is understood that the plant stripping machine may be used to strip many different species of plants. The hemp stripping machine allows a user to place a hemp plant into the machine wherein the leafy biomass is removed from the stalks. The user then retracts or pulls the stalk/stem portion upward from the machine while the stripped leafy biomass drops onto a conveyor belt which transports it for further processing.

FIG. 1 and FIG. 2 illustrate the hemp stripping assembly shown in perspective views. Hemp stripping machine 10 may include an elongated casing having two ends including, a pair of motor covers 30 and a pair of opposing central ramp portions 40 forming a top side of the casing and terminating at a longitudinal entry slot 48. The casing defines an interior volume for containing and somewhat directing the free leafy biomass. The casing may further include indented sides 43 to prevent accumulation of the free leafy biomass within machine 10 and help direct the free leafy biomass out of machine 10. The floor of the machine is either open or forms a ramp leading to an exit opening arranged optionally yet preferably over a conveyor assembly 110.

The machine 10 may be arranged over conveyor assembly 110 by supporting frame pieces positioned at both ends of the elongated case. Any number of frame pieces may be used to support machine 10. In some examples two frame pieces are used. In the illustrated embodiment, each frame piece may include a cross brace 16 and a pair of legs 14. Cross brace 16 may be an elongated body with two ends positioned horizontal in relation to the ground. Each leg 14 extends toward the ground from opposing ends of cross brace 16. In some examples, the legs may include a triangular shaped base with an upright beam extending from the base of the triangle to the apex of the triangle. The legs may be adjusted to any desired working height.

Conveyor assembly 110 may include belt 120 and frame 112 with legs 114. Belt 120 may be any suitable conveyor belt providing for a continuous loop of a sheet material around rollers on the frame of the conveyor assembly. The belt may be a continuous surface or composed of woven fibers of any suitable sheet material, for example thermoplastics, metal, rubber, fabric or leather.

Frame 112 may be in the shape of an elongated rectangle. Frame 112 may incorporate various numbers of legs 114 for support. In some embodiments, the frame includes three legs 114. Legs 114 may include two vertical beams parallel to each other on opposing lateral sides of frame 112. Cross-beams may be mounted extending between the vertical beams and perpendicular to the vertical beams. The cross-beams may also be parallel to each other. The frame 112 and legs 114 may be made of any suitable material, for example a metal or plastic.

FIG. 2 illustrates an embodiment with the hemp stripping machine 10 angled toward one side of conveyor assembly 110. This configuration permits easier access for a user on one side of the assembly to place a hemp plant into the hemp stripping machine.

FIGS. 3-7 illustrate views of hemp stripping machine 10 without the supporting frames and conveyor assembly 110. As illustrated, each opposing ramp portion 40 of casing includes a vertical outer side surface 42 ending at an upper edge where it transitions to top ramp 44. Top ramp 44 slopes diagonally inward and terminates at edge 46. The two ramp portions mirror each other resulting in a gap G1 between opposing parallel edges 46. The gap G1 defines entry slot 48. Ramp portions 44 may be in other geometries still defining an interior volume for containing and somewhat directing the free leafy biomass.

The casing may optionally include inner plates 32 to separate and protect motors positioned at the ends of the casing. For instance, plates 32 help prevent free leafy biomass from clogging the motors.

FIG. 6 and FIG. 7 illustrate a bottom view and a perspective bottom view of machine 10. As illustrated, arranged longitudinally below the respective ramp portions are a pair of rotating stripping assemblies 50 (shown in FIG. 9). As described in further detail below, each stripping assembly includes a shaft 51. A plurality of stripping members 60 extend radially and are spaced along the length of the shafts 51. In some examples, the stripping members 60 extend in only one direction from the shaft 51. In other examples, the stripping members 60 are arranged in pairs spaced 180 degrees around the circumference of the shaft 51. Each shaft 51 is rotationally driven by one or more power sources housed in one or more of the machine ends. In some examples, the one or more power sources is a power of motors 54. Each motor 54 is operably configured to independently rotate one of the shafts. The motor may be an AC motor. In additional embodiments, the motor may include a variable frequency drive for varying the motor input frequency and voltage to an AC motor.

The shafts 51 are spaced apart defining gap G2 between them. The shafts 51 are arranged below entry slot 48. The stripping members 60 radially overlap yet are longitudinally offset to alternate with each other, preventing them from hitting each other or the opposing shaft 51 while in use. The stripping members 60 extend from the pair of shafts 51 a radial distance sufficient to overlap within the gap G2. In some examples, the stripping members 60 may extend from the shafts 51 a distance equal to or greater than half the width of the gap G2. During operation, the shafts 51 counter rotate in relation to the other shaft so that the stripping members 60 pull material downward between the two shafts and rotate upward on the outward sides.

Stripping members 60 may be elongated fibers with their distal ends extending from the shaft 51. Stripping members 60 are somewhat rigid, yet stripping members 60 are also flexible enough that during operation of the machine, they may flail and strip a hemp stalk of leafy biomass without breaking off pieces of the hemp stalk. The stripping members 60 are preferably made of slightly flexible materials such as nylon forming a nylon cord. In another embodiment, the stripping members may be made of a rigid metal tine mounted to shaft 51 by a rubber boot allowing the metal stripping member to move/flail within the rubber mount. In other examples, the stripping members 60 may be composed of any composition of suitable materials, for example a rubber or a nylon/polyester blend. Stripping members can be solid or hollow.

FIGS. 6 and 7 provide the detailed views of frame 20 of hemp stripping machine 10. The perimeter of frame 20 may include a pair of side bars 22 and a pair of end plates 24. Each side bar 22 includes two ends. The side bars 22 may be arranged parallel in relation to each other. End plates 24 are mounted to and extend between the ends of both side bars 22. Frame 20 may optionally be in a generally rectangular shape. Each end plate 24 may include support holes 25 that allow machine 10 to be tilted along its longitudinal axis and selectively secured at an angled orientation.

Frame 20 may further include motor mounts 26 and bearing mounts 28. In some examples, the motor mounts 26 and bearing mounts 28 are secured to and extend between side bars 22. The motor mounts 26 and bearing mounts 28 may be secured using fasteners or welding. A motor mount 26 may be utilized to secure a motor 54 into position. Bearing mounts 28 may be utilized to secure pillow blocks 29 (illustrated in FIG. 8) in a position. Each pillow block 29 may contain a bearing with one of several types of rolling elements, including ball bearings, a cylindrical roller, a spherical roller, a tapered roller, or a metallic or synthetic bushing.

Frame 20 further defines an opening 70 in the floor of the machine. More specifically the perimeter of the opening 70 may be defined by side bars 22 and bearing mounts 28. During operation, when the leafy biomass is stripped off of the stalk by the stripping members 60, the leafy biomass drops through opening 70 and on to conveyor assembly 110.

FIG. 8 illustrates hemp stripping machine 10 with the pair of covers 30 and the pair of ramp portions 40 removed. FIG. 9 illustrates a stripping assembly 50 removed from the rest of the machine. Stripping assembly 50 includes shaft 51, motor 54, coupling 53 and a pair of pillow blocks 29. As described above, shaft 51 includes stripping members 60. Shaft 51 further includes a proximal end 55, central portion 56 and distal end 57. Proximal end 55 and distal end 57 of shaft 51 each extend through a respective pillow block 29 to rotatably mount the shaft in place. Proximal end 55 of shaft 51 extends through pillow block 29 and engages the drive shaft of motor 54 via coupling 53. Motor 54 is used to rotate shaft 51 around its longitudinal axis during operation of machine 10.

FIG. 10 provides an enlarged view of a portion of a shaft 51 with stripping members 60 extending radially along the length of the shaft. In other examples, stripping members 60 may extend along only a portion of shaft 51, for example along 75%, 50% or 25% of the shaft length.

FIG. 11A and FIG. 11B illustrate cross-sectional views of two examples of shaft 51. As illustrated in FIG. 11A shaft 51 may include openings 62, sleeves 64 and set screws 66. In the illustrated example, shaft 51 is a solid pipe with sleeves 64 extending across the interior diameter of shaft 51. Stripping members 60 may be extended through sleeve 64. Set screws 66 may be used to secure sleeves 64 and/or stripping members 60 within the shaft 51. The stripping members 60 are demonstrated as each formed of a single elongated fiber or bundle of fibers protruding radially from opposing ends of sleeve 64. The ends of stripping member 60 may extend 180 degrees from each other. Stripping members 60 possess enough rigidity to be linearly fed through the sleeves during the manufacturing of the machine or during replacement of damaged stripping members. In another example, in addition to or in replacement of the stripping members 60 extending through sleeve 64, stripping members 60 and sleeves 64 may extend through openings 62. This arrangement may result in stripping members in 90 degree increments around the circumference of shaft 51.

FIG. 11B illustrates an alternate embodiment of a cross-section of shaft 51. Stripping members 60′ extend through the openings in shaft 51. In this example, the stripping members 60′ do not extend through the entirety of the shafts interior. The base end of each stripping member is mounted to the shaft using a mounting back 64′ in the interior of the shaft. Various techniques may be used to secure the base of the stripping members 60′ to the mounting back 64′. In one embodiment, mounting back 64′ may be threaded to engage with threads on the base of the stripping members 60′. In yet another embodiment, mounting back 64′ may be a one way clamp with angled flanges preventing the stripping member from being pulled out of the mounting back 64′. In other alternatives, a friction fit, crimping or a variety of adhesives may be utilized to fasten the stripping member 60′ to the mounting back 64′.

FIGS. 12-13 illustrate another example of a shaft 151. Shaft 151 is comparable to shaft 51. The differences between shaft 151 and shaft 51 are discussed below in reference to shaft 151. Shaft 151 may include a shaft body 152, one or more elongated plates 158 and one or more stripping member components 161.

Shaft body 152 may define one or more indented portions or grooves 159. The indented portions 159 may extend along the entire length of the shaft body surface. Each indented portion 159 may be defined by a flat base 153 with diverging sides 155 broadly in the shape of the letter “U”. In some examples, the shaft body includes a pair of indented portions 159. The pair of indented portions 159 may be positioned 180 degrees apart around the circumference of the shaft body 152.

Each stripping member component 161 may be a single sheet of material defined by a center portion 163 with a pair of side edges 165. A plurality of stripping members 160 may extend away from the center portion 163 as fibers from the pair of side edges 165. The stripping members 160 may be cut from a single sheet of material. In some examples, the single sheet of material is flexible. In an alternative example, each stripping member 160 may be attached to the side edges 165 of the stripping member component 161. The stripping members 160 may be spaced evenly apart along the length of the stripping member component 161 or may be spaced in desired patterns or otherwise. Stripping members 160 are comparable to stripping members 60.

When clamped within the indented portion 159, the stripping member component 161 may be folded into substantially the same U-shape as the indented portion 159. When in the folded configuration, the side edges 165 allow the stripping member component 161 to be nested within the indented portion 159 of the shaft body and below the shaft surface. The folded configuration of the stripping member component 161 may cause the stripping members 160 to diverge outward and up in relation to each other. When mounted in the indented portion 159 of the shaft body 152, a plurality of openings in the base of the stripping member component 161 are aligned with the plurality of openings in the shaft body 152.

One or more plates 158 may include a flat upper surface and a bottom surface to nest within the indented portion 159 of the shaft body 152. In some examples, the upper surface of each plate is mounted flush with the outer surface of the shaft body 152. Plate 158 may include a plurality of fastener openings.

When assembled, the stripping member assembly 161 is securely sandwiched between the indented portion 159 of the shaft body 152 and one or more plates 158. When assembled, openings of the shaft body 152, stripping member component 161 and plate 158 are aligned, allowing fasteners, such as threaded screws or bolts, to extend downward through the plate 158, stripping member component 161 and shaft body 152, securing the pieces together. Various other known techniques, such as welding or adhesives, may be used to secure the plate 158, stripping member assembly 161 and shaft body 152 together.

Each indented portion 159 of shaft body 152 may receive one stripping component 161 and one plate 158. In alternative embodiments, any number of stripping components 161 and plates 158 may be received along the length of the indented portion 159. As illustrated in FIG. 12, each indented portion 159 may receive, along its length two plates 158. As described above, the stripping members may extend along only a portion of shaft 151, for example along 75%, 50% or 25% of the shaft length.

A technique for stripping hemp stalks of leafy biomass with the hemp stripping machine will now be described. During operation, the user may feed the hemp plant through the entry slot, inserting the stalks and leafy biomass between the shafts. As the stalks pass between the shafts, the stripping elements flail against the stalk, stripping the leafy biomass from the stalks and pulling the leafy biomass downward while leaving the stalks intact. The user then retracts the stalks against the pull of the stripping elements, while they continue to flail, further ensuring that the stalks are completely stripped. The stalks may then be collected for further processing. Concurrently, the leafy biomass falls through the opening in the floor of the machine, for instance onto a conveyor assembly. The leafy biomass passes to the end of the conveyor assembly where it can be collected and transferred for further processing.

The language describing the sides, surfaces and tops and bottoms of the disclosures components is not intended to be limiting in any manner. The language is solely included to aid in the understanding of the disclosure.

While the disclosure has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes, equivalents, and modifications that come within the spirit of the disclosure defined by the following claims are desired to be protected. 

1. A plant stripping machine comprising: a casing defining an interior volume; a pair of opposing central ramp portions forming a top side of the casing wherein the ramp portions extend downward and inward and terminate at opposing parallel edges defining a gap, wherein an entry slot is defined by the gap between the opposing edges of the ramp portions; a pair of shafts rotatably mounted within the interior volume of the casing, wherein each shaft includes a length, wherein the pair of shafts are parallel and spaced apart defining a gap between the shafts, and wherein the gap is aligned with the slot; a pair of motors at opposing ends of the casing, wherein each motor is operably configured to rotate a shaft, and wherein the shafts counter rotate in relation to each other; and a plurality of stripping members extending radially from and spaced along the length of each shaft, and wherein the stripping members extend from the shafts a distance equal to or greater than half the width of the gap.
 2. The plant stripping machine of claim 1, wherein the stripping members are flexible.
 3. The plant stripping machine of claim 1, comprising: a sheet of material defined by a center portion with a pair of side edges wherein a plurality of the stripping members extend away from the center portion as fibers from the pair of side edges; wherein at least one of the shafts defines a groove along the shaft's length; wherein at least one plate is configured to be secured within the groove; and wherein the center portion of the sheet of material is clamped within the groove by the at least one plate, and wherein the stripping members extend from the sheet on opposing sides of the plate.
 4. A plant stripping machine comprising: a casing defining an interior volume; a longitudinal slot defined in the top of the casing; a pair of shafts rotatably mounted within the interior volume of the casing, wherein each shaft includes a length, wherein the pair of shafts are parallel and spaced apart defining a gap between the shafts, and wherein the gap is aligned below the slot; one or more power sources operably configured to counter rotate the pair of shafts in relation to each other; a plurality of stripping members extending from and spaced along the length of each shaft, wherein the stripping members extend from the pair of shafts a radial distance sufficient to overlap within the gap; and wherein the pair of counter rotating shafts are operably arranged to engage and pull a plant with a stalk and leafy biomass which is fed through the slot to between the shafts, wherein the stripping members remove the leafy biomass from the stalk while leaving the stalk intact.
 5. The plant stripping machine of claim 4, wherein the one or more power sources is a pair of motors arranged at opposing ends of the casing, and wherein each motor independently rotates one of the shafts.
 6. The plant stripping machine of claim 4, wherein stripping members extending from the pair of shafts radially overlap yet are longitudinally offset to alternate with each other.
 7. The plant stripping machine of claim 4, wherein the stripping members extend a radial distance shorter than the width of the gap.
 8. The plant stripping machine of claim 4, comprising: a sheet of material defined by a center portion with a pair of side edges wherein a plurality of the stripping members extend away from the center portion as fibers from the pair of side edges; wherein at least one of the shafts defines a groove along an outer surface of the shaft along the shaft's length; a plate configured to be secured within the groove; and wherein the center portion of the sheet of material is clamped within the groove by the plate, wherein stripping members extend from the sheet on opposing sides of the plate.
 9. The plant stripping machine of claim 8, wherein the sheet of material is flexible.
 10. The plant stripping machine of claim 4, wherein each shaft has a plurality of openings defined in the shaft; where a sleeve extends through each opening; and wherein the stripping members are formed as fibers with each fiber secured in a sleeve so that opposing ends of the fiber protrude from opposing ends of the sleeve.
 11. The plant stripping machine of claim 4, wherein each stripping member extends through an opening in an outer surface of the rotating shaft, and wherein each stripping member is secured within the interior of the shaft.
 12. The plant stripping machine of claim 11, wherein the stripping members are formed as fibers with opposing ends of each fiber extending one hundred and eight degrees apart around a circumference of the shaft.
 13. The plant stripping machine of claim 4, wherein the stripping members are flexible.
 14. The plant stripping machine of claim 13, wherein the stripping members are made of nylon.
 15. The plant stripping machine of claim 4, wherein the stripping members are rigid metal tines.
 16. The plant stripping machine of claim 4 comprising: a pair of central ramp portions sloping diagonally inward into the interior of the casing and terminating at opposing parallel edges, and wherein the slot is defined by the gap between the edges of each of the ramp portions.
 17. A method comprising: feeding a portion of a plant having a stalk and leafy biomass downward through a slot of a plant stripping machine, the machine having a pair of counter rotating shafts arranged within the machine, wherein the pair of counter rotating shafts define a gap between the shafts and aligned with the slot; inserting the plant into the gap; engaging the plant with a plurality of stripping members extending radially from and spaced along a length of each shaft, wherein the stripping members flail against the plant, stripping the leafy biomass from the stalk while leaving the stalk intact; and retracting the stalk upward through the slot of the plant stripping machine.
 18. The method of claim 17 comprising: aligning the plant stripping machine at an angle to allow a user easier access to the slot.
 19. The method of claim 17, wherein the stripping members are flexible.
 20. The method of claim 17, comprising: a sheet of material defined by a center portion with a pair of side edges wherein a plurality of the stripping members extend away from the center portion as fibers from the pair of side edges; wherein at least one of the shafts defines a groove along the shaft's length; wherein at least one plate is configured to be secured within the groove; and wherein the center portion of the sheet of material is clamped within the groove by the at least one plate, and wherein stripping members extend from the sheet on opposing sides of the plate. 